Beill



(No Model.)

w. GAMBRI-LL & PI. RUSSEL.

LET QFPMEOHANISM FOR LO0M$.

No. 332,887; Patented 1365.22, 1885;

UNITED STATES PATENT OFFICE.

WILLIAM B. GAMBRILL AND PHILIP RUSSEL, OF WOODBERRY, MARYLAND.

LET-OFF MECHANISM FOR LOOMS.

SPECIFICATION forming part of Letters Patent No. 332.887, dated December 22, 1885.

Application filed June 2, 1884. Serial No. 133,497. (No model.)

To all whom it may concern.-

Be it known that we, WILLIAM B. GAM- BRILL and PHILIP RUssEL, both of Woodberry, in the county of Baltimore and State of Maryland, have invented certain Improvements in Let off Mechanisms for Looms, of which the following is a specification.

The object of this invention is to effect in a loom a regular and constant tension of the warp yarns or threads, and to enable the de-.

creasing size of the roll of yarn on the beam to be compensated for, whereby the desired number of picks may be at all times given to the half-inch of cloth.

Our invention consists of a certain improve ment in let-off mechanism for looms, as hereinafter described. If the warp-beam of a loom gives too much tension to the warp-yarn, the cloth is found with an increased number of picks to the halfinch, and if the tension of the yarn is reduced below the required point the cloth is made thin or with a reduced number of picks. Now, it is evident that with a full beam the threads are more easily unrolled than when the supply of thread on the said beam is nearly exhausted.

Our invention consists, therefore, in applying to the warp-beam tension regulating 'devices, which are under control of the attendant, and may be regulated by him so as to give the desired number of picks under all circumstances.

In the further description of our invention which follows reference is made to the accompanying drawings, forming apart hereof, and in which- Figure I is an exterior side view of the main parts of a loom providedlwith our improvements. Figs. II and III are views of parts of the invention.

A is the frame of the loom, and B the yarnbeam on which the threads or, which constitute the warp, are wound.

G is the cloth-roller on which the cloth I) is rolled. The lease-rods are denoted by c c and the shuttle-box by d. The lay forces the filling to the cloth-making point, and draws more E is a friction-block, the inner edge of which and it is lined with leather or other suitable material, h, to increase the friction between the parts. The pressure on the friction-block E is regulatedby means of a screw, F, which passes through a lug, j, fastened to the frame A. The screw F has a ratchet-wheel, F, and pawl i, to prevent a backward movement of the screw causedby the jarring of the machine.

In a recess,-k, in the block E is situated a curved plate, Z, which bears against the leather lining h of the said block.

G is a spring confined between screw F and the plate l. The object of theplate and spring is to make the pressure of the block E on the pulley D to some extent yielding. Supposing the loom to be in operation and the beam filled with yarn, the friction-block Eis forced into contact'with the friction-pulley until such friction is obtained as will give the proper number of picks to the halfinch of cloth. The manufacture of the cloth is continued until there are indications that the number of picks are being increased, when the screw F is slackened and the resistance which the beam.

offers to the unwinding of the warp reduced until the proper number of picks is re-established.

In the foregoing we have not described all the parts of the 100m or their operation, but only such as are necessarily affected by the operation of the invention.

We claim as our invention- The yarn-beam 13, having the circular rack e, shaft 9, pinion s on the shaft 9, in gear with the said circular rack, and friction-pulley D on the shaft 9, combined with the loom-frame having the threaded lug j, projecting from and forming a part thereof, screw F, which passes through the said threaded lug, curved block E, resting on the friction-pulley and provided with the recess 70, curved plate Z, situated in the recess is, and spring G, substantially as and for the purpose specified.

WM. B. GAMBRILL. PH JIP RUSSEL.

Witnesses:

Guns. B. CASSADY. WM. T. HOWARD. 

